Dyson Sphere Concept Creator and Project Orion Co-Lead Has Died

https://www.npr.org/2020/02/28/810433230/physicist-and-iconoclastic-thinker-freeman-dyson-dies-at-96″>Freeman Dyson has died at the age of 96.

In 1958, the Project Orion Pulsed Nuclear Propulsion Rocket was started and was led by Ted Taylor at General Atomics and physicist Freeman Dyson. Freeman took a year away from the Institute for Advanced Study in Princeton to work on the project.

In the 1960s, Project Orion was a major effort to use nuclear bombs to propel a massive spaceship. Researchers had found that a massive metal plate could survive a nuclear blast and the plate could be accelerated to very high speeds.

Exploding a bomb 25 meters away would only use 1% of the energy of the explosion.

If the nuclear device is encased in a radiation case of x-ray opaque material (uranium) with a hole in the top. This forces the x-rays to to exit only from the hole. Whereupon they run full tilt into a large mass of beryllium oxide (channel filler).

The beryllium transforms the nuclear fury of x-rays into a nuclear fury of heat. Perched on top of the beryllium is the propellant: a thick plate of tungsten. The nuclear fury of heat turns the tungsten plate into a star-core-hot spindle-shaped-plume of ionized tungsten plasma. The x-ray opaque material and the beryllium oxide also vaporize a few microseconds later.

The tungsten plasma jet hits square on the Orion drive pusher plate. The plate is designed to be large enough to catch all of the plasma. With the reference design of nuclear pulse unit, the plume is confined to a cone of about 22.5 degrees. About 85% of the nuclear device’s energy is directed into the desired direction instead of 1%.

Each charge accelerates the spacecraft by roughly 12 m/s. A 4,000 ton spacecraft would use 5 kiloton charges, and a 10,000 ton spacecraft would use 15 kiloton charges. For blast-off, smaller charges of 0.15 kt and 0.35 kt respectively would be used while within the Terra’s atmosphere. The air between the charge and the pusher plate amplifies the impulse delivered, so if you are not in airless space you can get away with a smaller kt yield.

Freeman Believed Other Problems Were More Important Than Climate Change

Many Concepts from a Brilliant Mind

Dyson had several innovations and concepts.
* the Dyson sphere, a thought experiment where advanced space-faring civilizations could make a megastructure that completely encompasses a star and captures a large percentage of its power output.

* Astrochicken is a Dyson design for a one-kilogram spacecraft. It would be self-replicating and could explore space more efficiently than a manned craft could due to its innovative mix of technology.

It would mix biology, artificial intelligence and modern microelectronics. It would be a blend of organic and electronic components. Astrochicken would be launched by a conventional spacecraft into space, like an egg being laid into space. Astrochicken would then hatch and start growing a solar-energy collector. The solar collector would feed an ion drive engine that would power the craft. Once Astrochicken entered a planet’s vicinity, it would collect material from the moons and rings of the planet, taking in nutrients. It could land and take off using an auxiliary chemical rocket similar to that used by bombardier beetles. It periodically transmit details of its journey when it could make radio contact with Earth.

* Dyson’s transform is a fundamental technique in additive number theory, which he developed as part of his proof of Mann’s theorem

* the Dyson tree is a hypothetical genetically-engineered plant capable of growing in a comet

* the Dyson series, a perturbative series where each term is represented by Feynman diagrams

* Dyson’s eternal intelligence is a means by which an immortal society of intelligent beings in an open universe could escape the prospect of the heat death of the universe by extending subjective time to infinity while expending only a finite amount of energy.

SOURCES- Youtube, Wikipedia, Project Rho
Written By Brian Wang, Nextbigfuture.com